kings motors gt 80

Maybe this will help, I have 2 of the balanced motors from Dax, they both arepowerful motors. I also have a real Grubee "80", and they blow the Grubee away.

I run a 40 tooth rear sprocket.

Good luck, I have never had any problems with Dax!cvlt1
 
I purchased a Silver Flying Horse Kit from Gas Bikes .. I believe it is a GT5 38mm stroke motor. I know there are a lot of different kits out there,, like PK80, 40mm stroke, 2 different pistons and 5-6 connecting rods out there,,, I seem to have the 38mm smaller piston and no marking copper color rod,, I would like to say that my cylinder was in good quality,, barely any casting flaws.

I have the slant head with spark plug towards rear of engine.
stock NT carb with needle clip in 2nd down from top out of 5 positions, the first carb they sent had all chinese markings on it and a 4 position needle, they sent me a new one cause plastic float leaked, new one has slight differences like 5 postion needle and different looking main jet.. I know that these carbs have a way to big.079 main jets and that can cause 4-stroking
I have a banana type expansion pipe,
stock cdi and magneto in 1 oclock postion and ohms out at 320
spark plug boot real crappy and has like this loose spring clip inside it,,, dont like it but get spark
tried all types of different spark plugs ,, no difference
running 32 to 1 synthetic mineral 2 stroke Bel Ray oil..
tried adjusting needle clip posistions,,, a little better a low throttle and rpms
i port matched the exhaust pipe flange to be more oval then small round
trimmed base gasket where there was overlapping but have not case matched to jug or done anything with intake except add o-ring to prevent leaking
bike has real good compression and lots of power,,, i never have to pedal,,, and starts right up even with out choke,,, never used choke yet
i live in Stroudsburg PA, and probably a little high here in elevation
**** Like I said,, when starting off under load and throttle it purrs good and smooth, as soon as it starts to rev up like when the pipe should be kicking in some powerband it just starts to break up and crackle and loose power and at 15-20mph half throttle no load cruising it does the same crackiling and popping.

and also what should i do with my dremel and light porting,, like i can see a good bit of piston in exhaust port a BDC which also means my transfer ports arent getting un covered all the way either,, and the intake is all overlapping and can see piston skirt at TDC.. and bottom case to cylinder jug transfers is also all overlapping not matched metal... please help as i read and hear all types of things to do and everyone says he or he is wrong ... confusing... just want it to run smooth from low to high and feel a powerband kick at like 5000 rpms... I think if i port matched everything and smooth the flow out thru engine should run better,,, dont know what to do about piston skirt on intake side and raise exhaust port a little,,, or use thick base gasket and sand down head ???? also should i just adapt a Walboro 15mm carb and adjust hi and low speed settings like on my 50cc scooter... please help
 
im port matching everything porting my piston (i have reed valves) walboro carb and sbp x chamber im haveing about the same troubles you are
 
i ride my bike dailey to work it pulls great but it wants to deisel bad when cold a little bettr when warmed up pulls hard up some pretty steep hills with just a little help i realy think its got a lot more in it
 
well i have engine tore down ported piston did a little port matching on tranfers took about a head gaskets worth off head takeing a break will try to put pics up after i put it back togeather all in all it looked realy good inside no scratches on cylender intake polished nicely light port work on trasfers exaust widend some i think i got a good one i also ordered a suzki 80 x chamber today will be here in about a week
 
Mine is up and running, so far so good. Ports looked good and overall was pretty clean for a China motor. Still want to get 2 tanks through it before I put the coals to it.
 

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No, only thing is it takes some time to warm up....have to leave the choke on longer than the other motors I have.
 
I have a gt80 on my bike. It runs fairly well. Not like I was hoping but it'll do 30 with a 240lb rider 44t sprocket. My motor diesels at wot as well. Does anyone who has torn apart one of these know which internals are being used? I have yet to tear mine down to see. Going to be doing some mods soon due to what I have just read on this thread. Thanks for all the info everyone.

http://motorbicycling.com/attachment.php?attachmentid=82814&d=1466133986
 
Hard to say what the end power and speed with this GT80 will be.
I do know I am throwing a KTM 50 together next though.
 
the x chamber that comes with this kit is very restictive get a sbp chamber i beleive this will help a lot i also removed the spacer between reed vavle and jug it helped a lot with throttle responce
 
I planned on removing the spacer (WTF?) from the intake and I kind of had a feeling that the poo poo pipe that came with it was indeed aptly named. I also had to add about 2.5in length to the intake to get it to fit the frame and I wonder if that didn't have a negative effect. It does four stoke at wot. I just torqued my front motor mount bolts in half inside the case so It'll be coming off the bike soon. Was thinking about putting it back into one of those Felt style integrated tank frames. They look a bit more sturdy than the grubee's with the hardmount. Have a feeling the frame I have it in now isn't going to cut it. This motor has already torqued 6 spokes and 2 front mounts. I will give this motor that, it is a low end monster!
 
just got done modding a suziki rm 60 x chamber for my bike got it installed and simi tuned shes twice as fast at least lots more top end i need to tune more to get bottom end back more than likely going from 36 to40 tooth cog rejet carb ill try to send a pic after while
 
I'm looking at this kit too. There seems to be a few discussions in the archives about this motor. One earlier adopter find metal shavings and poor workmanship, other owners seem to like it and have not had any issues. Some users suggest taking it apart and inspecting the engine as a good measure for any purchase.

I wonder if it is possible to get more than 4.5 HP out of it or if it can even get the 4.5 HP that they claim it to have.

Anyway, I hope that you can find the information that you need.

I bought the Silver Slant Kit for $119 from them and it was filled with metal shavings. I just purchased a Silver Horse 80/66C for$139.00 and it should be here Monday and Ill let you guys know how this one looks. Also lots of flashing on the ports that needs to be cleaned out.
 
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